<template>
  <div id="root">
    <div class="todo-container">
      <div class="todo-wrap">
        <MyHeader @addTodo="addTodo"/>
        <MyList :todos="todos" :checkTodo="checkTodo" :deleteTodo="deleteTodo"/>
        <MyFooter :todos="todos" @checkAllTodo="checkAllTodo" @clearAllTodo="clearAllTodo"/>
      </div>
    </div>
  </div>
</template>

<script>
import MyHeader from './components/MyHeader'
import MyFooter from './components/MyFooter'
import MyList from './components/MyList'

export default {
  name: 'App',
  components: {MyHeader, MyFooter, MyList},
  data() {
    return {
      todos: JSON.parse(localStorage.getItem('todos')) || []
    }
  },
  methods: {
    // 添加todo
    addTodo(todo) {
      console.log('我是 App 组件，我收到了数据：', todo)
      this.todos.unshift(todo)
    },
    // 勾选or取消勾选
    checkTodo(id) {
      this.todos.forEach(item => {
        if (item.id === id) {
          item.done = !item.done
        }
      })
    },
    deleteTodo(id) {
      this.todos = this.todos.filter(item => item.id !== id)
    },
    checkAllTodo(done) {
      this.todos.forEach(todo => {
        todo.done = done
      })
    },
    clearAllTodo() {
      this.todos = this.todos.filter(todo => !todo.done)
    }
  },
  watch: {
    todos: {
      handler(newValue) {
        localStorage.setItem('todos', JSON.stringify(newValue))
      },
      deep: true  // 开启深度监视
    }
  }
}
</script>

<style>
/* 公共的 */
body {
  background: #fff;
}

.btn {
  display: inline-block;
  padding: 4px 12px;
  margin-bottom: 0;
  font-size: 14px;
  line-height: 20px;
  text-align: center;
  vertical-align: middle;
  cursor: pointer;
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.2), 0 1px 2px rgba(0, 0, 0, 0.05);
  border-radius: 4px;
}

.btn-danger {
  color: #fff;
  background-color: #da4f49;
  border: 1px solid #bd362f;
}

.btn-danger:hover {
  color: #fff;
  background-color: #bd362f;
}

.btn:focus {
  outline: none;
}

.todo-container {
  width: 600px;
  margin: 0 auto;
}

.todo-container .todo-wrap {
  padding: 10px;
  border: 1px solid #ddd;
  border-radius: 5px;
}
</style>